JPS6017278B2 - Selection signal transmission method in electronic exchange - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a selection signal sending system in an electronic exchange Okuiso.

The markout method or the register sender method is widely used as an exchange method in electronic exchanges.

Among these, the present invention refers to an electronic exchange that employs the register sender method. This register sender method has the advantage of reducing the burden on the subscriber because it does not require the trouble of checking the dial tone each time the subscriber dials, unlike the markout method. Its main components are a subscriber terminal, a main link, and
A register trunk receives the dialed number from the subscriber, a sender trunk sends out dial pulses corresponding to the dialed number of the register trunk, that is, a selection signal, and receives the output of the sender trunk and transmits it via a trunk line. ,
It consists of a trunk line that transmits this to the downstream station. In this case, if the subscriber continuously sends selection signals at regular intervals, these trunks will be effectively utilized, but if the transmission of two consecutive selection signals takes a long time,
These trunks are held for a certain period of time, for example 5 seconds, to acquire the subscriber. Furthermore, since the number of digits in the selection signal transmitted by a subscriber varies, even after the subscriber transmits the final digit selection signal, these trunks are unable to receive the selection signal within a certain period of time. After confirming that no transmission is made, it is determined that this is the last digit. The trunk is also held during this time. In this case, if the number of digits of the selection signal to be transmitted is known in advance, such trunk reservation is not necessary, but this requires a large-scale memory device and is therefore difficult to implement. In any case, holding these trunks, especially register trunks and sender trunks, for long periods of time prevents other subscribers who wish to share these trunks from using them, resulting in poor line utilization.

If we want to prevent this usage efficiency from deteriorating,
A problem arises in that trunk equipment must be significantly increased. Therefore, an object of the present invention is to propose a selection signal sending system in an electronic exchange machine that eliminates the above-mentioned problems and can improve line utilization efficiency while maintaining the current scale. In accordance with the above object, the present invention includes a subscriber terminal, a register trunk that receives a selection signal from the subscriber terminal via a main link, a sender trunk that receives the selection signal sent from the register trunk as input,
and a trunk line for transmitting the selection signal from the sender trunk to the trunk line.
If the following selection signal is not received and detected within a predetermined period D for reconnecting the main link, the subscriber terminal is connected directly to the trunk trunk, and the subscriber terminal is directly connected to the trunk trunk and the register trunk and the a normal mode that releases the sender trunk to other subscriber terminals;
In the case where the subsequent selection signal is received and detected within the predetermined period D, the state of the connection change of the main link is:
If it is within the predetermined period B in which it is possible to continue receiving the subsequent selection signal without causing any pulse loss in the selection signal to be connected, the connection change of the main link is canceled and the original main link is reconnected. a return mode for returning to the connected state, and if the subsequent selection signal is received and detected within the predetermined period D and within the predetermined period C that follows the predetermined period B, the connection change of the main link is canceled. At the same time, the selection signal is processed in one of three modes: an alarm mode in which a busy tone is emitted to the subscriber terminal to prompt the subscriber terminal to transmit the selection signal again. be.

The present invention will be explained below with reference to the drawings.

FIG. 1 is a block diagram showing a general electronic exchange system to which the present invention is applied.

In this figure, 11 is a subscriber terminal, 12 is a main link, 1
3 is a register trunk that sequentially receives a selection signal from the subscriber 11 via link R; 14 is a sender trunk that receives the output of the register trunk 13 and sends out a selection signal in the form of a dial pulse; The trunk 14 serves to transmit the received selection signal to the exchange on behalf of the subscriber. Thereafter, it is transmitted to the downstream station 17 via the link S and the trunk trunk 15 . 16 is a trunk line.

The general operation of the electronic exchange system shown in FIG. 1 and the operation based on the method of the present invention will be explained with reference to the time chart shown in FIG.

First, assume that the subscriber terminal 11 dials a dial number, for example, "2" (column a in the period song in Figure 2).
)reference). This dial number "2" is received by the register trunk 13 as shown in Column b) of the synchronized eyebrow song. Furthermore, during the same period X, the signal is sent to the sender trunk 14 as shown in column c), and is sent from the trunk trunk 15 as shown in column d). That is, this period X,
indicates a period in which one selection signal is received by the register trunk 13 and sent to the trunk line 16 via the sender trunk 14 and trunk trunk 15. In this case, the number of "in" selection signals in the register trunk 13 and the number of "output" selection signals from the sender trunk 14 are determined by the central processing unit (CP) via the scanning device (SCN) 19.
U) If the numbers match, that is, if the number of digits in the received selection signal matches the number of digits sent out, conventionally it would be "waiting" and the trunk 13 , 14 and waits for the subsequent selection signal. However, according to the method of the present invention, the "waiting" period is eliminated, and after a certain period of compensation after sending the selection signal, the main link connection is changed, and the subscriber terminal 11
A new control method is adopted in which the trunk line and the trunk line 15 are directly connected via the link T.

Note that the period for compensation described above is extremely shorter than the period for determining the final digit described above, and corresponds to the period of inter-digit timing, so-called minimum pause.
However, in this case, during the main link connection change, when there is a conflict between the reception of the selection signal successively transmitted from the subscriber terminal 11 and the execution of the main link connection change, the central processing unit 1
The question arises as to how 8 should reconcile this conflict. The present invention also addresses such problems in the new control method described above. For this purpose, first, the above-mentioned compensation period in which the selection signal is not received or transmitted is changed to the main link connection change request period A (A in FIG. 2,
, n), and after the route of this period A, the central processing unit 18 completes the execution of the main ring connection change. This period is shown as main link reconnection completion period D in FIG. During this period D, one of the following modes is formed: first, normal mode, second, return mode, and third, alarm mode.

In the first normal mode, no selection signal arrives from the subscriber terminal 11 during main link connection change after period A, and connection change is performed normally. In other words, this case corresponds to a case where the necessary selection signals have been received for all digits, or a case where the connection change is completed by the dialing operation of the next digit. In addition, this main link connection change is similar to the main link connection change in normal exchange control, and multiple processing controls such as releasing the existing link and connecting a new main link are performed from the central processing unit to the main link (also called a communication path). ) Processing time for 12 (equivalent to period D)
is necessary. Also, in this normal mode, the register trunk 13 and sender trunk 14 are released to other subscriber terminals. In the second return mode, period A
The subscriber terminal 11 during the execution of the main link connection change in the later period D.
A selection signal from the main link has been received and detected, but the main link connection change has not yet been completed (during period B, which will be described later within period D), and it is not possible to return to the original selection signal reception state (return). Since this is a possible period, the connection change is canceled and the state returns to the original state of receiving and transmitting the selection signal. In the third alarm mode, a selection signal from the subscriber terminal 11 is received and detected during the main link connection change in period ○ after period A, but the connection change cannot be restored during the period (described later in period ○). Therefore, the selection signal sent to the trunk line 16 may be missing pulses. Therefore, in this alarm mode, the connection change is canceled and the process is switched to a process (alarm) for transmitting a busy tone to the subscriber. Note that this process itself is carried out as a busy process similar to that of normal plot dialing. Regarding the above period A, A and A2 in FIG. 2 are distinguished as follows.

Among the three modes mentioned above, the first/one mode, that is, the case where normal switching is performed, is the case after period A2, and the case where the second or third return or alarm mode occurs is after period A. This is the latter case. This second
In addition to explaining the above three modes with the diagram, especially period A
, the relationship with the control of the central processing unit 18 in the latter case will be explained using FIG. First, starting from period A2 in FIG. After a period D until the link connection change is completed, a transition is made to a period E.

During this period E, when control is performed normally, subscriber terminal 1
1 is directly connected to the trunk line trunk 15 by a link T (see FIG. 1) (see columns a) and d in period E in FIG. 2, which is a characteristic period of the present invention. It is. As a result, both the register and sender trunks are freed (column b in period E in Figure 2).
) and c)), allowing interruptions by other subscribers (not shown). That is, central processing unit 18 is enabled to process other calls. In other words, due to this interruption, the right to use both the register and sender trunks is transferred to the other subscriber. Note that these link connections are changed by the central processing unit 18.
It is carried out under the direction of By the way, in the method of the present invention, the conventional considerably long "waiting" period is eliminated and a new main link connection change request period is provided.

This is also the above-mentioned minimum pause period, but since processing specific to the present invention is performed during this period, in the present invention, this is intentionally referred to as the main link connection change request period. During this period, as mentioned above, the subscriber terminal 11
A case may occur (the second and third modes described above) where the subsequent selection signal from the central processing unit 18 conflicts with the main link reconnection request from the central processing unit 18. This is because, as mentioned above, in electronic exchanges, main link connection change is the same as main link connection change in normal exchange control, and multiple processing controls such as release processing of existing links and connection processing of new links are performed centrally. This is because processing time is required to carry out the processing from the main link 12 to the main link 12, and there is some time delay due to the opening and closing of the relay contacts, for example, due to the time required to pass through a so-called path selection relay. The case of this conflict will be explained with reference to period D following period D. In Fig. 2, in the case of the above-mentioned conflict, during period B, the main link connection change is in progress as described above, but if a selection signal is received and detected during this period, the original state is restored. This is the period during which growth is possible. During this period B, if a subsequent selection signal P is transmitted from the subscriber terminal 11 and a connection change request pulse (for example, a control command to the main link, etc.) is generated from the central processing unit 18 almost simultaneously, then this The request pulse is canceled, the current register trunk 13 continues to receive the selection signal P, and the sender trunk 14 sends out the selection signal. Furthermore, it is sent to the trunk line trunk 15. At this stage (period X2 in FIG. 2), the number of “in” selection signals (in the register trunk 13) and the
the number of outputs (in the sender trunk 14) matches,
As before, the main link connection change request period enters. Period A, later main link connection replacement completion period D
Regarding the time when the selection signal P is received and detected after the period B has elapsed and the period C in which the original state before the connection change cannot be recovered, that is, the state of the alarm mode described above, will be described in more detail. This will be explained using Figure 3.

Assume that when the aforementioned selection signal P is transmitted, the connection change request pulse is generated as indicated by Q shown in column b) of FIG. This reconnection request is valid when the state of the subscriber line (represented as selection signal P) is the loop closed state (logic "0" in column a) shown in column a) of FIG. 3, and the main link The connection is changed. When the request pulse Q falls, the loop of the sender trunk 14 is opened (column c) and disconnected from the logic "0" (column c).
logic “1”). At this time, the loop from the trunk trunk 15 to the downstream station 17 changes from closed (logic "0" in column d) to disconnected (logic "1" in column d). Further, the loop from this trunk trunk 15 to the subsequent station 17 is opened when the selection signal p) of the subscriber line (column a) is opened. As a result, when the selection signal P is sent from the trunk trunk 15, a pulse loss occurs in the selection signal P in the area indicated by the diagonal line U shown in column d). If the selection signal P with this missing pulse is sent to the downstream station 17, an erroneous connection will naturally occur. To prevent this, when a pulse is missing, a busy tone is sent to the subscriber, prompting the subscriber to dial again. In the example of FIG. 3 used in the above explanation, the pulse widths of the selection signals P received during period C are illustrated as being the same, but in reality there are many states in which selection signals are received, and this embodiment The examples are not limited.

In other words, the central processing unit 1 may receive data in the latter half of period B (as shown by the dashed-dotted line) or within period C (as shown by the dashed-double line), or depending on the number of lines accommodated by the exchange, etc.
8, the period C and the pulse width of the received selection signal P are not necessarily the same as shown by the solid line in the embodiment. Generally, the time required to change the connection of the main link 12 under the control of the central processing unit 18 (the time the hardware operates) is shorter than the pulse width of the selection signal P; pulse width)
There is a relationship of ≧(period C). Here, whether the selection signal has been received during the period C is determined by the central processing unit 18 through the scanning device 19 through a process of determining whether the selection signal has been received or detected. At the time of scanning by the scanning process to detect P (suitable example, scanning periodically),
By detecting the presence or absence of reception of a selection signal (the presence or absence of a loop), it can be determined whether the alarm mode is present or not. Thus, the reception detection of the selection signal P in each period B and C is not determined by the pulse width of the selection signal P, but is determined whether a loop is formed (for example, logic "0") or
This is done by determining whether the loop is broken (for example, logic "1").

The scanning process for reception detection will be described below. In order to detect the presence or absence of the pulse missing, the central processing unit 18, via the scanning device 19, uses a sampling signal V having a monovalent S interval (the pulse width of one selection signal is 64 mS (in the case of 1OPPS)), for example. The logical product of the output signal of the sender trunk 14 and the selection signal P is searched. The method of setting logic "0" and "1'' in this logical operation is as shown in Figure 3. This logical operation is performed immediately after the fall of the pulse Q shown in column b) of Figure 3. The result of the AND immediately after the fall of this pulse Q is logic “1”.
”, it is assumed that there was already a pulse missing just before that, and a busy tone is transmitted.If the pulse Q exists at a timing that does not cause such a pulse missing (usually most of the time) In this case (corresponding to the normal mode described above), the logic of the selection signal P immediately after the fall of the pulse Q is "0", and the result of the logical product is "0", and the pulse is missing. It is assumed that there is no.
As is clear from the above description, the periods A and A2 in FIG. 2 are merely explanations of different events in the same drawing as an example, and in reality, the normal mode is activated immediately after receiving one selection signal. The return mode is repeated each time a selection signal is received for each digit, the alarm mode is entered between a certain digit of a selection signal, or the alarm mode is entered as shown in Figure 2. Needless to say, various situations may occur, such as going through turn mode once and then entering normal mode.

As described above, according to the present invention, a selection signal sending system is realized that can significantly improve line utilization efficiency without increasing the number of trunk equipment.

[Brief explanation of the drawing]

Figure 1 is a block diagram showing a general electronic exchange system to which the method of the present invention is applied, Figure 2 is a time chart for explaining the operation of the electronic exchange system of Figure 1, and Figure 3 is the invention of the present invention. 3 is a time chart for explaining special operations in FIG. In the figure, 11 is a subscriber terminal, 12 is a main link, and 13 is a subscriber terminal.
14 is a sender trunk, 15 is a trunk line, 16 is a trunk line, and 18 is a central processing unit. Figure 1 Figure 2 Figure 3

Claims (1)

[Claims] 1 A subscriber terminal, a register trunk that receives a selection signal from the subscriber terminal via a main link, a sender trunk that receives the selection signal sent from the register trunk, and a register trunk that receives the selection signal from the sender trunk. In an electronic exchange having a trunk trunk for transmitting a selection signal to a trunk line, a predetermined period D for reconnecting the main link following a predetermined period A in which a selection signal subsequent to the selection signal does not arrive. a normal mode in which the subscriber terminal is directly connected to the trunk trunk when the subsequent selection signal is not received and detected within the period, and the register trunk and the sender trunk are released to other subscriber terminals; and the predetermined period. In the case where the subsequent selection signal is received and detected within D, the state of the connection change of the main link is such that the subsequent selection signal can be continuously received without causing a pulse drop in the subsequent selection signal. When the state is within the predetermined period B, the return mode is used to cancel the connection change of the main link and restore the original main link connection state. If the subsequent selection signal is received and detected within the subsequent predetermined period C, the connection change of the main link is canceled and a busy tone is emitted to the subscriber terminal, prompting it to send the selection signal again. A selection signal sending system in an electronic exchange, characterized in that the selection signal is processed under one of three alarm modes.